1. Field of the Invention
The present invention relates to an image processing device, and more particularly, to an image processing device, an image signal processing chip, and an ISP (Image Signal Processing) chain constructing method, which can reconstruct an ISP chain structure.
2. Description of the Related Art
In general, an image processing device is connected to an image sensor, receives sensor data which is an electrical signal (raw data) corresponding to an outside image output from the image sensor, and outputs RGB data, YUV data, or encoded image data corresponding to the sensor data. Such an image processing device includes a variety of ISP functional blocks distinguished by image signal processing functions.
FIG. 1 is a diagram illustrating an ISP chain structure in an image processing device according to the related art.
An ISP chain means a set of ISP functional blocks connected to each other in a constant order. For example, as shown in FIG. 1, N ISP functional blocks 10-1, 10-2, 10-3, . . . , and 10-N are sequentially connected to construct a single ISP chain.
Here, each of the ISP functional blocks 10-1, 10-2, 10-3, . . . , and 10-N performs one of image signal processing functions such as noise reduction, edge enhancement, gamma correction, and color interpolation.
Referring to FIG. 1, the ISP chain is constructed in the order of the first ISP functional block 10-1, the second ISP functional block 10-2, the third ISP functional block 10-3, . . . , and the N-th ISP functional block 10-N. The ISP functional blocks 10-1 to 10-N of having a fixed execution order sequentially perform signal processes to acquire a final image processing result ISP Output.
The image processing device is mounted on a mobile terminal so as to cause the mobile terminal to serve as an imaging device. That is, the image processing device is mounted on a mobile terminal such as a mobile phone, a PDA, and an MP3 player and is configured to convert external images into electronic data and to store the electronic data. In this case, the image processing device requires a variety of image signal processes depending on product applications of the mobile terminals.
However, as shown in FIG. 1, after the ISP chain structure of the image processing device is determined and is embodied as a chip, it is not possible to change the order, thereby making it difficult to implement image signal processing functions optimized for various product applications.